Here is an idea. Everyone grab a hold of all the basic religious scripture and celebrated philosophical writings that they can, spend some time studying them, cast aside all cultural predispositions, and use the light of reason to cast a critical gaze upon the collected wisdom of the ages in an honest search for a path towards an ethically sound and spiritually fulfilled life.
Guess what, that is called 'liberalism'. That is what the definition of a religious liberal is. Apply the same line of thought to politics, and you have what is called a political liberal.
Unfortunately, we in the modern world have gotten into a fairly interesting political debate after the early success of free market capitalism transformed into industrialized oppression of a newly formed 'working class' at the turn of the last century. The reaction to this rather nebulous and yet obvious system of serfdom and resultant economic theory, communism, would unfortunately morph into a horrific system of bureaucratic oppression. Even though both of these inherently flawed ideas are now over a century old, it is still the fact that communism is newer than capitalism, and so it is widely viewed that the 'conservative' is one who supports the free market, and the 'liberal' is one that supports government intervention in an economic market. The answer to the question of government intervention in economics seems to involve a concept that has somehow become a four letter word in recent debate, that is 'nuance'. In reality, both major political parties in the United States support a wide variety of programs of government intervention ranging from corporate welfare and farm subsidies to social security and nationalized health insurance plans.
The honest truth of the matter is that if you subject our current political and social institutions to rational scrutiny and speak your mind concerning the fruits of your research independent without fear of the majority viewpoint then you are a liberal. Even if you don't have any sushi on the dinner table and hate government economic intervention you are a liberal. Thought you were a conservative? Well too bad.
I have a feeling that right now quite a few small-government liberals have been hoodwinked by political conservatives. They have been told that liberalism is socialism, when in fact it is an appeal to reason over what one is told. The political concept of 'conservatism' has been all dressed up with a bizarre infusion of the financial concept of 'fiscal conservatism', which ought to be relabeled 'fiscal sanity'. Holding onto ones money bears little resemblance to holding onto antiquated ideals and corrupt institutions.
Quite a few hawkish liberals have been hoodwinked by social conservatives. After the success of Mahatma Gandhi and Martin Luther King Jr. it has been easy to play semantic games and try to say that liberalism means nonviolence. Well, I will note that Bertrand Russell, one of the fathers of modern axiomatic mathematics and modern propositional calculus, was a pacifist. But liberalism is just an appeal to rationality and reason over deeply ingrained cultural institutions. Try to tell one of the revolutionary fighters of 1776 that they aren't liberals.
Even though David Hume put a damper on some of the most lofty goals of the enlightenment, and even though modern philosophy has abandoned the Leibnitzian dream of calculating ethical solutions on an abacus, the spirit of the enlightenment burns in the modern world, our universities and laboratories have multiplied, and the first born child of political liberalism, the United States of America, burns as bright as ever. We have scramjet engines, a 70 TFLOP supercomputer, and robots on Mars.
But we need to stop this linguistic decay of the word 'liberal' before the progress of science and reason is ultimately put into jeopardy. If one is to survey the current state of the modern industrialized world, a certain level of socialism has become an institution. If you think that it is flawed or corrupt, then you might be a liberal. If you think that our current system is not providing enough for the disenfranchised, then you might be a liberal. To be bluntly honest, if you are thinking, then you might be a liberal. This isn't just about government intervention in the economy.
If however, you think that evolution is scientifically on par with creationism, or perhaps you think that men are more intellectually capable than women, or maybe you condemn Islamic terrorism while cheering for Eric Rudolph, then you have a pretty serious problem. Consult the writings of the founding fathers on the subject of 'charlatan priests', and after you get over the initial embarrassment you can join the debate.